Tonight, at 8:30 pm local time, houses and commercial buildings all over the world will suddenly go dark. No, it’s not a global power outage, it’s Earth Hour! Started in 2007, this annual event has become a worldwide phenomenon, educating people about the threat of climate change, and encouraging a commitment to more sustainable behavior.

In a message to the world on the eve of the seventh Earth Hour, UN Secretary General Ban Ki-moon has set the agenda for this year’s hour of inspiration. “We participate with an undimmed determination to take action on climate change,” he said. “Everyone has a role to play. Governments need to provide the political will, businesses can contribute solutions, and civil society, especially young people, can mobilize global action. Together, let’s do our part and shed light on common sense answers for a cleaner, greener world.” Turning out the lights for an hour might seem strange and a little pointless, but participating in Earth Hour makes a powerful statement that can last far longer than 60 minutes.

In Uganda, the world’s first Earth Hour Forest was allocated with 2,700 hectares of land, challenging Ugandans to fill it with 500,000 trees to fight against the 6,000 hectares of deforestation that occurs in the country every month. Standard Chartered Bank (250,000 trees), the Ugandan Minister of Water Environment (1,000 trees) and many individuals have taken on the challenge.

The Russian parliament passed a long-awaited law to protect the country’s seas from oil pollution in December, after the voices of 120,000 Russians were presented to the government during the “I Will If You Will” campaign for Earth Hour 2012.

The Former President of Botswana and Earth Hour Botswana coordinators Wena Environmental Education and News Trust, recently launched a project called ‘One Million Trees-Plant For Life’ as part of Earth Hour’s I Will If You Will campaign. The project will rehabilitate degraded lands through the planting of more than one million trees over four years in Botswana.